Zinc status of healthy elderly adults: response to supplementation

The zinc status of 53 healthy elderly subjects was evaluated. The dietary Zn intake estimated by 24-h recall was 9.2 mg/d and 65% of subjects had intakes less than two-thirds of the RDA. Mean serum Zn concentration (13.0 mumol/L) and urinary Zn excretion (7.0 mumol/d) were normal. The Zn content of platelets, mononuclear cells, and polymorphonuclear cells was 5.8, 147, and 135 nmol/10(9) cells, respectively. Seventeen subjects were supplemented for 28 d with 30 mg Zn/d. The mean concentration of Zn in serum and urine increased 24% and 2.5-fold, respectively. Zn content of platelets and leukocytes did not change with Zn supplementation. The concentration of visceral proteins (ie, albumin, prealbumin, transferrin, and retinol-binding protein) and immunoglobulins (ie, IgG, IgA, and IgM) did not change with Zn supplementation. The data indicate that aging per se does not necessarily imply poor Zn status.